Table 1.
Demographic and clinicopathological characteristics of patients with ypT0–2N0 rectal cancer
| Variable | Chemo group (n = 58) | Non-chemo group (n = 51) | P-value |
|---|---|---|---|
| Agea (years) | 50.4 ± 10.5 | 59.4 ± 12.3 | <0.001 |
| Sex | 0.891 | ||
| Male | 36 (62.1) | 31 (60.8) | |
| Female | 22 (37.9) | 20 (39.2) | |
| BMIa (kg/m2) | 24.3 ± 3.5 | 24.6 ± 3.0 | 0.636 |
| Distance between tumor and the anal vergea (cm) | 4.5 ± 2.0 | 3.9 ± 1.9 | 0.071 |
| CEA (ng/mL) | 0.815 | ||
| ≤5 | 41 (70.7) | 35 (68.6) | |
| >5 | 17 (29.3) | 16 (31.4) | |
| Clinical T stage | 0.982 | ||
| cT2 | 3 (5.2) | 3 (5.9) | |
| cT3 | 44 (75.9) | 38 (74.5) | |
| cT4 | 11 (18.9) | 10 (19.6) | |
| Clinical N stage | 0.409 | ||
| cN0 | 12 (20.7) | 14 (27.5) | |
| cN1–2 | 46 (79.3) | 37 (72.5) | |
| Pre-operative chemotherapy | 0.536 | ||
| Capecitabine | 25 (43.1) | 25 (49.0) | |
| CAPOX | 33 (56.9) | 26 (51.0) | |
| Time interval (weeks) | 0.295 | ||
| <6 | 14 (24.1) | 10 (19.6) | |
| 6–8 | 23 (39.7) | 15 (29.4) | |
| >8 | 21 (36.2) | 26 (51.0) | |
| ASA class | 0.074 | ||
| I | 5 (8.6) | 1 (2.0) | |
| II | 50 (86.2) | 42 (82.3) | |
| III | 3 (5.2) | 8 (15.7) | |
| Type of surgery | 0.139 | ||
| APR | 33 (56.9) | 36 (70.6) | |
| LAR | 25 (43.1) | 15 (29.4) | |
| Laparoscopic vs open surgery | 0.436 | ||
| Fully laparoscopic | 35 (60.3) | 27 (52.9) | |
| Open from the beginning | 23 (39.7) | 24 (47.1) | |
| Post-operative complication | 0.827 | ||
| Yes | 10 (17.2) | 8 (15.7) | |
| No | 48 (82.8) | 43 (84.3) | |
| Tumor differentiation | 0.440 | ||
| Well differentiated | 2 (3.5) | 2 (3.9) | |
| Moderately differentiated | 33 (56.9) | 29 (56.9) | |
| Poorly differentiated | 10 (17.2) | 4 (7.8) | |
| Unknown | 13 (22.4) | 16 (31.4) | |
| Post-operative T stage | 0.138 | ||
| ypT0 | 22 (37.9) | 29 (56.9) | |
| ypT1 | 4 (6.9) | 2 (3.9) | |
| ypT2 | 32 (55.2) | 20 (39.2) | |
| Tumor response | 0.179 | ||
| Severe response | 35 (60.3) | 37 (72.5) | |
| Moderate response | 23 (39.7) | 14 (27.5) | |
| Perineural invasion | 3 (5.2) | 0 (0) | 0.246 |
| Number of LN retrievala | 13.6 ± 7.4 | 11.4 ± 7.4 | 0.129 |
| Duration of enterostomya,c (months) | 28.4 ± 17.5 | 7.6 ± 1.7 | 0.023 |
| Follow-upb (months) | |||
| 51.5 (37.0–70.3) | 50.0 (37.0–68.0) | 0.642 |
aThese values are presented as mean ± standard deviation. bthis value is presented as median followed by range in parentheses; other values are presented as number of patients followed by percentage in parentheses. cFourteen patients had temporary enterostomy, of which five and nine were in the chemo and non-chemo groups, respectively.
BMI, body mass index; CEA, carcinoembryonic antigen; CAPOX, capecitabine and oxaliplatin; ASA, American Society of Anesthesiologists; APR, abdominoperineal resection; LAR, low anterior resection; LN, lymph nodes.